In a typical network computing environment, a hierarchy of servers often exists that are networked together. While this hierarchy of servers may be as few as two servers, it can also involve many servers. These servers are often located in physically unique locations. In a network, a server represents the application code (hosted on server computer) that runs on an operating system and a client (hosted on a client computer) represents the code run in any number of different applications that can run on many different operating systems. A client application can interface with the server to backup or archive data on the server machine.
In a network computing environment, copying the data is performed in order to protect the data files from corruption on the local client computer's hard drive, accidental deletion of a file, and other problems. A storage system between the servers on the network can back-up and store the data, and can also manage the data stored in the volumes. In standard networks having a number of levels of interconnected servers, the volumes are typically physical volumes, such as disk drives or tape drives, that are locally attached to each server. These locally attached storage devices must be maintained and managed at each unique location.
This traditional model of a storage system in a computer network has limitations in the fact that it is administratively burdensome to have operators at each server site to maintain the physical volumes. While the cost per megabyte of storing data in physical tape libraries is relatively inexpensive compared to other storage media, the maintenance and administration of tape libraries may be costly. Examples of some administrative tasks would be managing the inventory of tapes within the library including removing full tapes from the library, cleaning drives, adding additional scratch tapes to the library, and other routine maintenance tasks. Reducing the number and locations of physical storage media would reduce both the complexity and cost of this administration and maintenance.